well, the darn thing is out

[gmwillys]

It's getting hard to find, but the permatex brown bottle shellac was always a go to for sealing up the valve cover gaskets. Too often the mounting hardware is over torqued, and it deforms the cover to where it is not flat enough to seal against the gasket and block.

Lucas additive is good stuff. I knew a lot of truck drivers and fleets that swore by it.

Speaking of additives, I have personally tried this product, and highly recommend it first for your firearms, then for your vehicles;

http://www.militec-1.com/

The stuff works great on all firearms, when applied per the directions. I tested it out on my muzzleloader, and now it takes just a total of two patches to clean and seal. It does work very well in my Springfield 40 cal. as well. I have used it in air compressors and on my big block Chrysler derby cars through the years, and have been impressed with the results.